Swimming pool cover

ABSTRACT

A swimming-pool cover is composed of a series of sets of profiled sections connected to one another over the length by flexible connection element ( 2 ), each set being composed of two rigid longitudinal end profiled sections ( 3, 4 ). The rigid end profiled sections ( 3, 4 ) are assembled by a forced watertight fitting together ( 5 ) of the complementary male ( 3 ) and female ( 4 ) ends.

The present invention relates to a swimming pool cover composed of aseries of sets of profiled members connected to one another over thelength by a flexible connection element, each set being composed of twoend rigid longitudinal profiled sections with at least one central rigidlongitudinal profiled section.

Such a cover is known from the patent U.S. Pat. No. 3,683,428. Thisdocument discloses slats connected to one another by alternatingflexible fasteners making it possible to fold the cover in a concertina.The top of the join between the slats between which the fasteners aresituated is covered with a flexible membrane such as self-adhesivematerial. This type of cover resolves a major part of the disadvantagesof the majority of swimming pool covers. This is because, generally,covering and uncovering the swimming pool is an operation that is sodifficult and tiresome that the owner no longer covers the swimmingpool. Consequently the long periods of dormancy of the cover result inthe accumulation of isolated coloring, algae and lime, which thenrequire the use of chemical products to remedy the deterioration of thecover. This use of chemical products is obviously not to be recommendedin the environment of a swimming pool. Covers suspended on railsgenerally procure mediocre insulation against the loss of heat. Thepatent U.S. Pat. No. 3,683,428 counteracts all these disadvantages byoffering a floating insulating cover which remains in place whilstwithstanding the inevitable small waves on the surface of the water byvirtue of the flexible connections and which can easily be used and iseasy to manipulate on a daily basis, consequently assisting its use andavoiding the “long periods of dormancy”.

Nevertheless, one drawback of this cover, even if it is available inpreassembled units, is that it does not procure easy installation for aperson skilled in the art, who must lay the slats on the water and cutthem to the width of the swimming pool before assembling them. This isbecause assembling the fasteners on the edge of the slats of the cover,synchronizing the alternation of fasteners between the preassembledunits in order to maintain the folding of the cover in a concertina andthen again laying the flexible membrane on the top of the fastenerbetween two successive slats are tasks which are complicated anddifficult for a person skilled in the art. In addition, manufacturingsuch a cover requires various operations such as the manufacture of theslats, the preparation of the preassembly, the manufacture of thefasteners and packaging in an assembly kit.

One objective of the invention is to mitigate these drawbacks, whilstprocuring the same advantages, by procuring a swimming-pool cover in theform of sets of preassembled profiled sections whose installation doesnot require easier intervention, and whose manufacture and preparationare simplified.

This is because the invention procures a swimming-pool cover wherein thesaid rigid end profiled sections comprise respectively a malelongitudinal end and a female longitudinal end, said rigid longitudinalend profiled sections of two consecutive sets being assembled by aforced watertight fitting together of the complementary male and femaleends, said flexible connecting element between said profiled sections ina flexible polymer possessing an interface on each side with the rigidprofiled section.

Assembling the cover according to the invention consequently entailseasy cutting to size (to the width of the swimming pool) of severalprofiled sections in one go and fitting together which is simple for aperson skilled in the art. In addition, the manufacture of the swimmingpool cover according to the invention is a relatively simple step, forexample, which comprises only a single molding and more particularlyextrusion step. The watertight forced fitting together of thecomplementary ends avoids any accumulation of lime or algae which mightoccur.

The state of the art, in particular in the patents DE 19646117 C and EP1 233 125 A1, also reveals covers for swimming pools consisting ofhollow slats, generally comprising internal profiled sections, thehollow slats each possessing a male coupling at one end and a femalecoupling at the other end. The male and female couplings are designed tobe slid into each other and procure in this way a well known and easyassembly of the cover. It must nevertheless be remarked that theassembly area of the swimming-pool cover fulfils the role of a join andthat this area must consequently have a certain flexibility of movementin order to be able to follow the movement of the waves on the surfaceof the water. This type of assembly, although easy, through its verynature has the disadvantage of not being watertight so that wateraccumulates around the assembly area and sometimes stagnates inside theprofiled sections when the ends are not plugged. This causes anaccumulation of lime and impairs the flexibility of the assembly at theconnection.

When the swimming pool has access steps integrated in a rounded shape,the hollow slats constituting the cover must be cut either aslant or insteps. In the case where the slats are cut aslant, it is possible toblock the ends with prefabricated obturation elements since, accordingto the cutting angle, the stoppers will have to have differentdimensions. This approximation used to follow the curvature of the edgeof the swimming pool presents, in addition to the disadvantage ofcomplicating the plugging of the slats, another major disadvantage. Theslats, slipped into one another at the time of assembly, are not fixedto one another. As soon as the cut is made and the slats are assembledthey are always free for a reciprocating movement. The contour that theassembled cover must consequently describe is not the one obtained as afinal result because of the longitudinal sliding of the slats withrespect to one another. In the case where the slats are cutperpendicularly with respect to the length, it is possible to plug theends with prefabricated obturation elements. The major disadvantage ofthe sliding of the slats with respect to one another is however stillpresent in this case and the cutting of the cover results once again ina lack of finish due to the approximation used to follow the curvatureof the edge of the swimming pool. In both cases of cutting profiledsections, the fact that the profiled sections are not fixed to oneanother does not make it possible to ensure that an oblique orperpendicular cutting line produced across various consecutive profiledsections will be maintained since nothing ensures the alignment of atleast one of the profiled sections.

In some cases, these slats are procured from transparent plastic on thetop surface (in contact with the atmosphere) and black plastic on thebottom surface (in contact with the water). This arrangement of twocolors of plastic makes it possible to profit from a greenhouse effectin order to heat the water in the swimming pool. Unfortunately, the factthat the plastic on the top surface of the slat is transparent alsocauses an increase in algae in the profiled sections when the ends ofthe hollow slats are not plugged and at the assembly area and theappearance of condensation. This accumulation of algae occurs in placeswhich are not very accessible to cleaning, impairs the aestheticappearance and presents a risk of contamination of the water in theswimming pool.

The swimming-pool cover according to the invention does not suffer froman accumulation of algae at the assembly area. This is because theassembly of the cover according to the invention is a forced fittingwhich procures a watertight assembly area in which no accumulation ofalgae or lime is possible. The joint having the role of resisting themovement of the waves on the surface of the water is provided in theswimming-pool cover according to the invention not by the assembly ofthe male and female fittings but by the flexible connection elementsbetween the rigid longitudinal profiled sections.

In a particular embodiment in which the profiled sections of theswimming-pool cover according to the invention are solid, cutting aslantno longer poses any problem. In addition, the profiled sections beingfixed to one another, no reciprocating movement in length is possible.This enables the cut made on various consecutive profiled sections tokeep its profile.

In another particular embodiment, the sets of profiles connected to oneanother by the flexible connection elements are obtained by molding andpreferably by extrusion. These two manufacturing techniques given by wayof example embodiment of the invention are well known and very simpletechniques which can also be automated. Through such a manufacturingmethod, the swimming-pool cover does not have to be packaged with theseassembly elements. Consequently the swimming-pool cover according to theinvention is a cover fabricated in a single step, which does not requireany packaging step and which is simple to store.

In addition, in a preferential embodiment of the swimming-pool coveraccording to the invention, at least one of said rigid longitudinalprofiled sections having a first surface (Sa) and a second surface (Se)situated on each side of the horizontal plane joining the flexibleconnection elements, will have said first surface smaller than saidsecond surface. Typically said central rigid profiled sections andpreferably the end rigid profiled sections will also have a firstsurface smaller than the second surface. This asymmetry in the surfacesenables the rigid profiled sections to fulfill the role of solarcollectors and to heat the water in the swimming pool.

The rigid profiled sections used in the swimming-pool cover according tothe invention will be hollow or solid and preferably made from polyvinylchloride. The flexible connection elements will for their partpreferably be made from polyurethane. The aforementioned materials arematerials suiting very well the manufacture of rigid profiled sectionsand flexible membranes, in particular in the context of co-extrusion,and being particularly well suited to the application of theswimming-pool cover according to the invention.

Other characteristics, details and advantages of the invention willemerge from a reading of the descriptive memorandum made with referenceto the accompanying drawings given by way of non-limiting example and inwhich:

FIG. 1 is a view in section of a set of profiled sections of theswimming-pool cover according to the invention,

FIG. 2 is a view in section of an assembly of sets of profiled sectionsillustrated in FIG. 1,

FIG. 3 is a view from above of a swimming pool which presents anon-limiting example of application of the embodiment of swimming-poolcover according to the invention.

A preferential embodiment of a set of profiled sections according to theinvention is represented by a view in section in FIG. 1. This setcomprises solid profiled sections connected to one another over thelength by a flexible connection element (2). The set is composed of tworigid longitudinal end profiled sections (3, 4) and a succession of fiverigid longitudinal central profiled sections (1). The rigid end profiledsections (3, 4) comprise respectively a male longitudinal end (3) and afemale longitudinal end (4). The assembly as such sets is illustrated inFIG. 2. The end longitudinal rigid profiled sections (3, 4) of twoconsecutive sets are assembled by a forced watertight fitting together(5) of the complementary male (3) and female (4) ends.

FIG. 2 also presents the assembly of the preferential embodimentillustrated in FIG. 1 in which the surfaces situated on each side of thehorizontal plane joining the flexible connection elements are notidentical. The surface in contact with the water Se (the lower surfacewith respect to said plane defined above) is larger than the surface incontact with the atmosphere Sa (the upper surface with respect to saidplane). During the day, the sun heats, to a temperature Ta, the surfaceSa, which in this case fulfils the role of heat absorption surface. Therigid profiled sections will preferably be dark in color in order toincrease the heat absorption capacities of the rigid profiled sections.The temperature of the water designated here Te is less than thetemperature of the atmospheric air Ta during the day. This temperaturegradient creates a heat flow which moves towards the surface having alower temperature, in this case Se of temperature Te, obeying the wellknown laws of heat transportation and diffusion. The surface Se is inthis case what is referred to as the restoration surface. This transferof heat from the surface Sa to the surface Se is possible only if thesurface Sa is less than or equal to the surface Se. During the night,the contrary case presents itself, the temperature Te is greater thanthe temperature Ta. On the other hand the surface Sa is always less thanthe surface Se. Consequently the transfer of heat from the surfacepossessing the highest temperate (Se to Te) cannot take place towardsthe surface possessing a lower temperature (Sa to Ta) since Sa issmaller than Se. In this case, Sa therefore does not fulfill the role ofrestoration surface. It must obviously be remarked that zero loss ofheat is impossible to obtain in absolute terms given the physicalphenomena of diffusion and the thermodynamic laws which govern everyreal system. The cover according to invention therefore has the dualadvantage of being able to pick up the heat procured by the sun in orderto transmit it to the water when the external temperature is greaterthan the temperature of the water (daytime) and to reduce the loss ofheat during the night.

It is obvious that this surface ratio example is given by way ofnon-limiting example and that the top surface can be equal to the bottomsurface, whether or not the profiled section is symmetrical with respectto said plane.

Another application of the swimming-pool cover according to theinvention would consist of procuring hollow profiled sections, notclosed at the ends, in order to heat the water in the swimming pool bysimple circulation of swimming-pool water in the profiled sections.

FIG. 3 presents a particular application of the swimming-pool coveraccording to the invention. In this figure, the advantage with regard tothe finish afforded by the swimming-pool cover of the invention (3B or3C) emerges clearly compared with the finish procured by a swimming-poolcover of the state of the art (3A). The swimming-pool cover according tothe invention can comprise various types of rigid profiled sections.These may be hollow (3B) or solid (3C), the assembly can comprise analternation of sets of hollow and solid profiled sections whatever thenumber of consecutive hollow sets or consecutive solid sets. In order toafford a solution to the problem of finish at the edges of roundedswimming pools, the cover may be composed of a series of consecutivesets comprising hollow profiled sections all along the rectangular partof the swimming pool and a series of consecutive sets comprising solidprofiled sections in order to facilitate the finishing of the roundedpart, as described above.

The swimming-pool cover according to the invention can also comprisenarrower profiled sections (3B or C) than that which was achievable forother swimming-pool covers belonging to the state of the art (3A) giventhat the joins between the profiled sections of the state of art alltook on water. Consequently it was impossible to ensure the floatationof very narrow profiled sections which would have been able to procure abetter finish in the rounded parts. The swimming-pool cover according tothe invention makes it possible to fabricate very narrow profiledsections since the elastic junction between the profiled sections isperfectly watertight and therefore increases the bearing surface of thecover on the water, consequently making it possible to obtain anapproximation as close as possible to follow the curvature of theswimming pool.

1. A swimming-pool cover composed of a series of sets of profiledsections connected to one another over its length by a flexibleconnection element, each set being composed of two rigid longitudinalend profiled sections, said rigid end profiled sections comprisingrespectively a male longitudinal end and a female longitudinal end, saidlongitudinal rigid end profiled sections of two consecutive sets beingassembled by a forced watertight fitting together of the complementarymale and female ends, said flexible connection element between saidprofiled sections being a flexible polymer possessing an interface oneach side with the rigid profiled section.
 2. A swimming-pool cover asclaimed in claim 1, wherein a central longitudinal rigid profiledsection is disposed between two end longitudinal rigid profiledsections.
 3. A swimming-pool cover as claimed in claim 1, wherein thesets of profiled sections connected to one another by said connectionelement are obtained by molding.
 4. A swimming-pool cover as claimed inclaim 1, wherein the sets of profiled sections connected to one anotherby said connection element are obtained by co-extrusion.
 5. Aswimming-pool cover as claimed in claim 1, wherein at least one of saidlongitudinal rigid profiled sections possessing a first surface and asecond surface situated on each side of the horizontal plane joining theflexible connection elements has said first surface smaller than saidsecond surface.
 6. A swimming-pool cover as claimed in claim 2, whereinthe central rigid profiled section is hollow.
 7. A swimming-pool coveras claimed in claim 1, wherein at least one of the end rigid profiledsections is hollow.
 8. A swimming-pool cover as claimed in claim 1,wherein said central or end longitudinal rigid profiled section issolid.
 9. A swimming-pool cover as claimed in claim 1, wherein saidcentral longitudinal rigid profiled sections and said end longitudinalrigid profiled sections are made from polyvinyl chloride.
 10. Aswimming-pool cover as claimed in claim 1, wherein said flexibleconnection elements are made from polyurethane.